Crystal structure, Hirshfeld surface analysis and PIXEL calculations of a 1:1 epimeric mixture of 3-[(4-nitrobenzylidene)amino]-2(<i>R,S</i>)-(4-nitrophenyl)-5(<i>S</i>)-(propan-2-yl)imidazolidin-4-one
Bibliographic record
Abstract
A 1:1 epimeric mixture of 3-[(4-nitrobenzylidene)amino]-2( R,S )-(4-nitrophenyl)-5( S )-(propan-2-yl)imidazolidin-4-one, C 19 H 19 N 5 O 5 , was isolated from a reaction mixture of 2( S )-amino-3-methyl-1-oxobutanehydrazine and 4-nitrobenzaldehyde in ethanol. The product was derived from an initial reaction of 2( S )-amino-3-methyl-1-oxobutanehydrazine at its hydrazine group to provide a 4-nitrobenzylidene derivative, followed by a cyclization reaction with another molecule of 4-nitrobenzaldehyde to form the chiral five-membered imidazolidin-4-one ring. The formation of the five-membered imidazolidin-4-one ring occurred with retention of the configuration at the 5-position, but with racemization at the 2-position. In the crystal, N—H...O(nitro) hydrogen bonds, weak C—H...O(carbonyl) and C—H...O(nitro) hydrogen bonds, as well as C—H...π, N—H...π and π–π interactions, are present. These combine to generate a three-dimensional array. Hirshfeld surface analysis and PIXEL calculations are also reported.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.002 | 0.002 |
| Bibliometrics | 0.003 | 0.009 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".